yaffs Reactoring WIP

Signed-off-by: Charles Manning <cdhmanning@gmail.com>

1 files changed, 105 insertions, 0 deletions

diff --git a/yaffs_bitmap.c b/yaffs_bitmap.c
new file mode 100644
index 0000000..c7e9e8c
--- /dev/null
+++ b/yaffs_bitmap.c
@@ -0,0 +1,105 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "yaffs_bitmap.h"
+#include "yaffs_trace.h"
+/*
+ * Chunk bitmap manipulations
+ */
+
+static Y_INLINE __u8 *yaffs_BlockBits(yaffs_Device *dev, int blk)
+{
+	if (blk < dev->internalStartBlock || blk > dev->internalEndBlock) {
+		T(YAFFS_TRACE_ERROR,
+			(TSTR("**>> yaffs: BlockBits block %d is not valid" TENDSTR),
+			blk));
+		YBUG();
+	}
+	return dev->chunkBits +
+		(dev->chunkBitmapStride * (blk - dev->internalStartBlock));
+}
+
+void yaffs_VerifyChunkBitId(yaffs_Device *dev, int blk, int chunk)
+{
+	if (blk < dev->internalStartBlock || blk > dev->internalEndBlock ||
+			chunk < 0 || chunk >= dev->param.nChunksPerBlock) {
+		T(YAFFS_TRACE_ERROR,
+		(TSTR("**>> yaffs: Chunk Id (%d:%d) invalid"TENDSTR),
+			blk, chunk));
+		YBUG();
+	}
+}
+
+void yaffs_ClearChunkBits(yaffs_Device *dev, int blk)
+{
+	__u8 *blkBits = yaffs_BlockBits(dev, blk);
+
+	memset(blkBits, 0, dev->chunkBitmapStride);
+}
+
+void yaffs_ClearChunkBit(yaffs_Device *dev, int blk, int chunk)
+{
+	__u8 *blkBits = yaffs_BlockBits(dev, blk);
+
+	yaffs_VerifyChunkBitId(dev, blk, chunk);
+
+	blkBits[chunk / 8] &= ~(1 << (chunk & 7));
+}
+
+void yaffs_SetChunkBit(yaffs_Device *dev, int blk, int chunk)
+{
+	__u8 *blkBits = yaffs_BlockBits(dev, blk);
+
+	yaffs_VerifyChunkBitId(dev, blk, chunk);
+
+	blkBits[chunk / 8] |= (1 << (chunk & 7));
+}
+
+int yaffs_CheckChunkBit(yaffs_Device *dev, int blk, int chunk)
+{
+	__u8 *blkBits = yaffs_BlockBits(dev, blk);
+	yaffs_VerifyChunkBitId(dev, blk, chunk);
+
+	return (blkBits[chunk / 8] & (1 << (chunk & 7))) ? 1 : 0;
+}
+
+int yaffs_StillSomeChunkBits(yaffs_Device *dev, int blk)
+{
+	__u8 *blkBits = yaffs_BlockBits(dev, blk);
+	int i;
+	for (i = 0; i < dev->chunkBitmapStride; i++) {
+		if (*blkBits)
+			return 1;
+		blkBits++;
+	}
+	return 0;
+}
+
+int yaffs_CountChunkBits(yaffs_Device *dev, int blk)
+{
+	__u8 *blkBits = yaffs_BlockBits(dev, blk);
+	int i;
+	int n = 0;
+	for (i = 0; i < dev->chunkBitmapStride; i++) {
+		__u8 x = *blkBits;
+		while (x) {
+			if (x & 1)
+				n++;
+			x >>= 1;
+		}
+
+		blkBits++;
+	}
+	return n;
+}
+